portable

## Scanning for Auto Feature Sample Hits

If you measure an Auto Feature that uses sample hits, PC-DMIS prompts you to take those sample hits during measurement routine execution. Instead of taking just a few individual hits with your portable arm, however, you can now scan the surface with the probe to retrieve multiple hits very rapidly on each surface. This helps to improve your accuracy.

Some features, such as an Auto Circle, have one sample plane. Other auto features, such as Auto Angle Point or Auto Corner Point, have multiple sample planes. To scan a surface, press the button on your portable machine that begins retrieving hits from the controller, then pass the probe over the surface for as long as you like. PC-DMIS will read in multiple hits. When you release the button and finish scanning the surface, PC-DMIS prompts you to take the next set of sample hits on the next surface. Continue this process until you have scanned all necessary sample hits on all surfaces.

Rules of Scanning for Sample Hits

- You cannot scan for multiple sample planes in one scan segment. In other words, you can’t scan sample hits around corners. When you scan for sample hits, each scan must remain on a single surface. If a feature needs sample hits from more than one surface, such as a corner point feature that uses three surfaces, each surface needs its own scan.

- You cannot scan for sample hits and then measure a feature using the same scan segment. When scanning sample hits prior to actually scanning the feature to measure it, you should perform a scan segment for each surface needing sample hits, and then a separate scan segment for the actual feature measurement.

- When scanning the actual feature, not the sample hits, you can perform the feature measurement in a single scan. For example, for an Auto Square Slot, you will scan all four sides in one continuous segment.

For information on Auto Features and sample hits, see the "Creating Auto Features" chapter in the PC-DMIS Core documentation.

Registry Entries for Hard Probe Scanning

There are several registry entries in the PC-DMIS Settings Editor that control how when points are read into PC-DMIS from your portable arm's controller. The following registry entries are in the HardProbeScanningInFeatures section:

- MinDeltaBetweenPointsInMM - Sets the minimum distance (in millimeters) that your probe must pass before a new hit gets sent from the controller to PC-DMIS.

- MinTimeDeltaBetweenPointsInMilliseconds - Sets the minimum time (in milliseconds) that must pass before PC-DMIS takes a new hit.

- MaxPointsForAFeature - Sets the maximum number of points needed for a feature. Any points read into PC-DMIS from the controller beyond this maximum number are ignored.

For information on these registry entries, start your PC-DMIS Settings Editor, and press F1 to access its online Help. Then navigate to the appropriate topics.